Triiodothyronine augmentation of selective serotonin reuptake inhibitors in posttraumatic stress disorder

There is considerable comorbidity of major depression and posttraumatic stress disorder (PTSD), and antidepressants have been reported to be effective in treating PTSD. Addition of triiodothyronine (T3) to ongoing antidepressant treatment is considered an effective augmentation strategy in refractory depression. We report the effect of T3 augmentation of antidepressants in patients with PTSD.

T3 (25 microg/day) was added to treatment with a selective serotonin reuptake inhibitor (SSRI) (paroxetine or fluoxetine, 20 mg/day for at least 4 weeks and 40 mg/day for a further 4 weeks) of 5 patients who fulfilled DSM-IV criteria for PTSD but not for major depressive disorder (although all patients had significant depressive symptoms). The Clinician-Administered PTSD Scale, the 21-item Hamilton Rating Scale for Depression, and the Clinical Global Impressions-Severity of Illness scale were administered every 2 weeks, and self-assessments were performed with a 100 mm visual analog mood scale.

In 4 of the 5 patients, partial clinical improvement was observed with SSRI treatment at a daily dose of 20 mg with little further improvement when the dose was raised to 40 mg/day. This improvement was substantially enhanced by the addition of T3. Improvement was most striking on the Hamilton Rating Scale for Depression.

T3 augmentation of SSRI treatment may be of therapeutic benefit in patients with PTSD, particularly those with depressive symptoms. Larger samples and controlled studies are needed in order to confirm this observation.